United Nations High Commissioner for Refugees Ruud Lubbers has called on Iran to prepare to aid "future victims" of a possible war in the region, notably refugees from Afghanistan, the state news agency IRNA said Sunday.

Lubbers said such a conflict was "probable" and asked Iran to do its utmost, in a conversation late Saturday with Iranian Foreign Minister Kamal Kharazi, IRNA said.

According to local press reports thousands of Afghans have been moving towards the border with neighboring Iran, which is officially closed, and many have already crossed secretly.

Around 1,000 have arrived in the Afghan border town of Zarandj, while 500 others are waiting in the Pakistani town of Qila Sefed, both neighboring the Iran's southeastern province of Sistan-Baluchistan, according to the UNHCR.

"Those arriving are not yet coming in masses. In Afghanistan, people are leaving the towns to go to the country or to the mountains. As soon as the Americans attack, they will rush to the borders," a UNHCR official told AFP.

But the organization is expecting between 200,000 and 300,000 refugees and the Iranian authorities, in particular the Red Crescent, are setting up camps on the border, and are ready to receive 200,000 people.

But the deputy head of the immigration office at the interior ministry, Mohammad-Reza Rostami, quoted by the state news agency IRNA said: "Iran can not do it all alone."

The ministry also made an appeal to international organizations and foreign countries to help Iran, which already has more than two million refugees on its soil.

In a statement on the eve of his arrival in Tehran, British Foreign Secretary Jack Straw said London would offer assistance of some 36 million dollars, spread around the various neighbors of Afghanistan. Other donor countries, including Germany, France, Italy, Canada and Japan, have also offered support.

Bruno Jochum of the French-based charity Medecins sans Frontieres (Doctors without Borders - MSF), told AFP that the group could staff and equip two dispensaries, catering for 30,000 people, and distribute enough water for 90,000.

The UNHCR says refugees coming across the border face a terrible shortage of water as the region experiences a third straight year of drought -- TEHRAN (AFP)